U.S. patent application number 11/258126 was filed with the patent office on 2006-04-27 for system for detecting mis-connected state between communication lines for multi-type air conditioner and method thereof.
This patent application is currently assigned to LG Electronics Inc.. Invention is credited to Se-Dong Chang, Jae-Heuk Choi, Song Choi, Hyung-Soo Kim, Kwang-Woon Kim, Sung-Hwan Kim, Yoon-Been Lee, Jeong-Eon Oh.
Application Number | 20060086104 11/258126 |
Document ID | / |
Family ID | 35636779 |
Filed Date | 2006-04-27 |
United States Patent
Application |
20060086104 |
Kind Code |
A1 |
Chang; Se-Dong ; et
al. |
April 27, 2006 |
System for detecting mis-connected state between communication
lines for multi-type air conditioner and method thereof
Abstract
A system for detecting a mis-connected state between
communication lines for a multi-type air conditioner and a method
thereof. The system comprises an indoor unit pipe temperature
detection unit for detecting a temperature of an indoor unit pipe,
and a microprocessor for controlling an opening of an electronic
expansion valve based on a temperature detected by the indoor unit
pipe temperature detection unit, comparing a temperature response
characteristic of the indoor unit pipe with a preset temperature
response characteristic of a normal indoor unit pipe based on an
opening of the electronic expansion valve, and thereby judging
whether the communication lines are mis-connected to one another or
not. An indoor unit from which the mis-connection has been
generated is fast detected, and error information is displayed.
Accordingly, the mis-connected state between the communication
lines is restored, thereby preventing a damage of the system due to
the mis-connection.
Inventors: |
Chang; Se-Dong;
(Gyeonggi-Do, KR) ; Kim; Kwang-Woon; (Seoul,
KR) ; Lee; Yoon-Been; (Seoul, KR) ; Kim;
Hyung-Soo; (Seoul, KR) ; Kim; Sung-Hwan;
(Seoul, KR) ; Oh; Jeong-Eon; (Seoul, KR) ;
Choi; Jae-Heuk; (Seoul, KR) ; Choi; Song;
(Seoul, KR) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Assignee: |
LG Electronics Inc.
|
Family ID: |
35636779 |
Appl. No.: |
11/258126 |
Filed: |
October 26, 2005 |
Current U.S.
Class: |
62/129 |
Current CPC
Class: |
F24F 11/30 20180101;
F25B 2313/023 20130101; F25B 2313/0314 20130101; F24F 3/065
20130101; F25B 13/00 20130101; F25B 2600/2513 20130101; F24F
2140/20 20180101; F25B 2500/06 20130101; F25B 49/005 20130101; F25B
2313/0253 20130101 |
Class at
Publication: |
062/129 |
International
Class: |
G01K 13/00 20060101
G01K013/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 26, 2004 |
KR |
85918/2004 |
Claims
1. A system for detecting a mis-connected state between
communication lines of a multi-type air conditioner, comprising: an
indoor unit pipe temperature detection unit for detecting a
temperature of an indoor unit pipe; and a microprocessor for
controlling an opening of an electronic expansion valve based on a
temperature detected by the indoor unit pipe temperature detection
unit, comparing a temperature response characteristic of the indoor
unit pipe with a preset temperature response characteristic of a
normal indoor unit pipe based on the opening of the electronic
expansion valve, and thereby judging whether communication lines
are mis-connected to one another or not.
2. The system of claim 1, wherein the indoor unit pipe temperature
detection unit comprises: an inlet temperature detection unit for
the indoor unit pipe for detecting an inlet temperature of the
indoor unit pipe; and an outlet temperature detection unit for the
indoor unit pipe for detecting an outlet temperature of the indoor
unit pipe.
3. The system of claim 2, wherein the microprocessor calculates a
superheating based on the detected inlet temperature of the indoor
unit pipe and the detected outlet temperature of the indoor unit
pipe, and compares the calculated superheating with a preset
superheating thereby to judge whether the communication lines are
mis-connected to one another.
4. The system of claim 3, wherein the superheating is a difference
value between an outlet temperature of the indoor unit pipe
detected by the indoor unit pipe outlet temperature detection unit
and an inlet temperature of the indoor unit pipe detected by the
indoor unit pipe inlet temperature detection unit.
5. The system of claim 1, wherein the microprocessor compares the
temperature pattern of the indoor unit pipe detected for a preset
time with a preset temperature pattern of the indoor unit pipe,
thus to judge whether the communication lines are mis-connected to
one another.
6. The system of claim 5, wherein if the detected temperature
pattern of the indoor unit pipe is not consistent with a preset
inlet temperature pattern of the indoor unit pipe, the
microprocessor displays error information indicating a
mis-connected state between the communication lines.
7. The system of claim 1, wherein the microprocessor calculates a
superheating, that is, a difference value between the detected
inlet temperature of the indoor unit pipe and the detected outlet
temperature of the indoor unit pipe, compares the calculated
superheating with a preset superheating, compares the detected
temperature pattern of the indoor unit pipe with a preset
temperature pattern of the indoor unit pipe, and if the two
temperature patterns are not consistent with each other, displays
error information indicating a mis-connected state between the
communication lines.
8. The system of claim 1, further comprising: a display unit for
outputting error information indicating a mis-connected state
between the communication lines.
9. The system of claim 8, wherein the display unit includes a
screen, a display lamp and a buzzer.
10. The system of claim 1, further comprising: a storage unit for
storing a preset temperature response characteristic of the indoor
unit pipe according to an opening of the electronic expansion
valve.
11. The system of claim 10, wherein the response characteristic
stored in the storage unit includes an inlet temperature of the
indoor unit pipe, an inlet temperature pattern of the indoor unit
pipe, an outlet temperature of the indoor unit pipe, an outlet
temperature pattern of the indoor unit pipe, or a superheating
pattern.
12. A method for detecting a mis-connected state between
communication lines of a multi-type air conditioner, comprising:
operating an arbitrary outdoor unit and plural indoor units
connected to the outdoor unit; detecting a temperature response
characteristic of an indoor unit pipe according to an opening of an
electronic expansion valve; judging whether the detected response
characteristic is consistent with a preset response characteristic;
if so, displaying a normally-connected state between communication
lines and performing a normal operation; if the detected response
characteristic is not consistent with the preset response
characteristic, stopping the system and displaying error
information indicating a mis-connected state of the communication
lines on an additional display unit.
13. The method of claim 12, further comprising: storing a
temperature response characteristic of a normal indoor unit pipe
which is preset by an experiment.
14. The method of claim 12, wherein the response characteristic
includes an inlet temperature of the indoor unit pipe, an inlet
temperature pattern of the indoor unit pipe, an outlet temperature
of the indoor unit pipe, an outlet temperature pattern of the
indoor unit pipe, a superheating obtained by deducting the indoor
unit pipe inlet temperature from the indoor unit pipe outlet
temperature, or a superheating pattern.
15. The method of claim 14, wherein in the step of judging whether
the detected response characteristic is consistent with a preset
response characteristic, a superheating is calculated based on the
inlet temperature of the indoor unit pipe and the outlet
temperature of the indoor unit pipe, and the calculated
superheating is compared with the preset superheating.
16. The method of claim 14, wherein in the step of judging whether
the detected response characteristic is consistent with a preset
response characteristic, the inlet temperature of the indoor unit
pipe is compared with a preset inlet temperature of the indoor unit
pipe, and the outlet temperature of the indoor unit pipe is
compared with a preset outlet temperature of the indoor unit
pipe.
17. The method of claim 14, wherein in the step of judging whether
the detected response characteristic is consistent with a preset
response characteristic, a superheating is calculated, the
calculated superheating is compared with a preset superheating, and
the detected inlet temperature pattern of the indoor unit pipe is
compared with a preset inlet temperature pattern of the indoor unit
pipe.
18. The method of claim 14, wherein in the step of judging whether
the detected response characteristic is consistent with a preset
response characteristic, a temperature pattern of the indoor unit
pipe detected for a certain is compared with a preset temperature
pattern of the indoor unit pipe.
19. The method of claim 14, wherein in the step of judging whether
the detected response characteristic is consistent with a preset
response characteristic, the temperature pattern of the indoor unit
pipe detected for a certain is compared with a preset inlet
temperature pattern of the indoor unit pipe.
20. The method of claim 14, wherein in the step of judging whether
the detected response characteristic is consistent with a preset
response characteristic, a superheating is calculated and the
calculated superheating is compared with a preset superheating.
21. The method of claim 14, wherein in the step of judging whether
the detected response characteristic is consistent with a preset
response characteristic, a superheating is calculated, the
calculated superheating is compared with a preset superheating, and
the detected inlet temperature pattern of the indoor unit pipe is
compared with a preset inlet temperature pattern of the indoor unit
pipe.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a multi-type air
conditioner, and more particularly, to a system for detecting a
mis-connected state between communication lines for a multi-type
air conditioner capable of preventing a damage of the system by
judging a mis-connected state between communication lines based on
a temperature response characteristic of an indoor unit refrigerant
pipe according to an opening of an electronic expansion valve, and
a method thereof.
[0003] 2. Description of the Background Art
[0004] Generally, an air conditioner serves to control a
temperature, a humidity, air stream, and a clean degree for a
comfortable indoor circumstance. The air conditioner is classified
into an integral-type air conditioner and a separated-type air
conditioner according to a unit construction. The integral-type air
conditioner is constructed as an indoor unit and an outdoor unit
are received in a single case. On the contrary, the separated-type
air conditioner is constructed as an outdoor unit constituted with
a compressor and a condenser is separated from an indoor unit
constituted with an evaporator. Additionally, there is an air
conditioner for cooling and heating capable of selectively
performing a cooling operation and a heating operation by switching
a flow path of a refrigerant by a flow path switching valve
provided at the air conditioner. Recently, a multi-type air
conditioner having a plurality of indoor units for cooling or
heating each space of an indoor room is being increased. The
multi-type air conditioner is constructed as a plurality of outdoor
units each having a plurality of compressors corresponding to a
load of the indoor unit are connected to one another in
parallel.
[0005] FIG. 1 is an exemplary view showing an outdoor unit of a
multi-type air conditioner in accordance with the background
art.
[0006] As shown, the multi-type air conditioner comprises a
plurality of outdoor units (11a.about.11n), and a plurality of
indoor units (not shown).
[0007] Each outdoor unit 11a.about.11n comprises a first compressor
13a and a second compressor 13b constructed as one pair, a four-way
valve 21 for switching a flow path of a refrigerant, an outdoor
heat exchanger 25 for heat-exchanging a refrigerant, and a common
accumulator 27 for providing a gaseous refrigerant to the first
compressor 13a and the second compressor 13b.
[0008] A discharge pipe 15 for discharging a refrigerant is
provided at each upper region of the first compressor 13a and the
second compressor 13b. Also, a suction pipe 17 connected to the
common accumulator 27 for sucking a refrigerant is provided at each
lower region of the first compressor 13a and the second compressor
13b. An oil balancing pipe 19 for flowing oil with balance is
connected between the first compressor 13a and the second
compressor 13b.
[0009] Each compressor is provided with an oil separator 31 and a
check valve 33 at the discharge side thereof. Also, each separator
31 is provided with an oil returning path 35 for returning oil to
the suction side of each compressor.
[0010] Each check valve 33 is provided with a four-way valve 21 for
switching a flow path of a refrigerant at a lower side thereof. One
port of the four-way valve 21 is connected to the outdoor heat
exchanger 25, another port thereof is connected to the common
accumulator 27, and the other port thereof is connected to a
connection pipe 41 connected to the indoor unit.
[0011] The outdoor heat exchanger 25 is provided with a receiver 37
at one side thereof along a flow direction of a refrigerant. The
receiver 37 and the connection pipe 41 are respectively provided
with a service valve 43a and a service valve 43b at one side
thereof. Each one side of the service valves 43a and 43b is
connected to a main refrigerant pipe 45 for connecting the outdoor
units 11a.about.11n one another.
[0012] FIG. 2 is an exemplary view showing a multi-type air
conditioner having an arbitrary outdoor unit and a plurality of
indoor units connected to the outdoor unit in accordance with the
background art.
[0013] As shown, the multi-type air conditioner comprises an
outdoor unit and a plurality of indoor units connected to the
outdoor unit. The outdoor unit is connected to the plural indoor
units by communication lines, thereby controlling an air
conditioning of the plural indoor units.
[0014] In case that the multi-type air conditioner is installed in
the same building, a plurality of outdoor units can be connected to
a plurality of indoor units by communication lines crossed to one
another. Accordingly, a mis-connection between the communication
lines may occur.
[0015] FIG. 3 is an exemplary view showing a mis-connected state
between communication lines in a multi-type air conditioner in
accordance with the background art.
[0016] As shown, an indoor unit 1 receives a refrigerant from an
outdoor unit A, and receives an operation control command from an
outdoor unit B. Also, an indoor unit 4 receives a refrigerant from
the outdoor unit B, and receives an operation control command from
the outdoor unit A. Accordingly, if a mis-connection between the
communication lines of the outdoor units occurs due to a cross
connection therebetween, a control signal of one outdoor unit is
transmitted to an indoor unit controlled by another outdoor unit.
Therefore, the system is stopped while being operated thus to cause
the user's inconvenience and to cause the system to be mechanically
damaged.
BRIEF DESCRIPTION OF THE INVENTION
[0017] Therefore, an object of the present invention is to provide
a system for detecting a mis-connected state between communication
lines of a multi-type air conditioner capable of preventing a
damage of the system by judging a mis-connected state between
communication lines based on a temperature response characteristic
of an indoor unit pipe according to an opening of an electronic
expansion valve, and a method thereof.
[0018] To achieve these and other advantages and in accordance with
the purpose of the present invention, as embodied and broadly
described herein, there is provided a system for detecting a
mis-connected state between communication lines of a multi-type air
conditioner, comprising: an indoor unit pipe temperature detection
unit for detecting a temperature of an indoor unit pipe; and a
microprocessor for controlling an opening of an electronic
expansion valve based on a temperature detected by the indoor unit
pipe temperature detection unit, comparing a temperature response
characteristic of the indoor unit pipe with a preset temperature
response characteristic of a normal indoor unit pipe according to
an opening of the electronic expansion valve, and thereby judging
whether or not the communication lines are mis-connected to one
another.
[0019] To achieve these and other advantages and in accordance with
the purpose of the present invention, as embodied and broadly
described herein, there is also provided a method for detecting a
mis-connected state between communication lines of a multi-type air
conditioner, comprising: operating an arbitrary outdoor unit and
plural indoor units connected to the outdoor unit; detecting a
temperature response characteristic of an indoor unit pipe
according to an opening of an electronic expansion valve; judging
whether the detected response characteristic is consistent with a
preset response characteristic; if so, displaying a
normally-connected state between the communication lines and
performing a normal operation; if the detected response
characteristic is not consistent with a preset response
characteristic, stopping the system and displaying error
information indicating a mis-connected state between the
communication lines on an additional display unit.
[0020] The foregoing and other objects, features, aspects and
advantages of the present invention will become more apparent from
the following detailed description of the present invention when
taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The accompanying drawings, which are included to provide a
further understanding of the invention and are incorporated in and
constitute a part of this specification, illustrate embodiments of
the invention and together with the description serve to explain
the principles of the invention.
[0022] In the drawings:
[0023] FIG. 1 is an exemplary view showing an outdoor unit of a
multi-type air conditioner in accordance with the background
art;
[0024] FIG. 2 is an exemplary view showing the multi-type air
conditioner having an arbitrary outdoor unit and a plurality of
indoor units connected to the outdoor unit in accordance with the
background art;
[0025] FIG. 3 is an exemplary view showing a mis-connected state
between communication lines in the multi-type air conditioner in
accordance with the background art;
[0026] FIG. 4 is an exemplary view showing a construction of a
system for detecting a mis-connected state between communication
lines for a multi-type air conditioner according to the present
invention;
[0027] FIGS. 5A, 5B and 6 are exemplary views respectively showing
a response characteristic when the communication lines are normally
connected to one another and a response characteristic when the
communication lines are mis-connected to one another based on an
indoor unit pipe temperature when the multi-type air conditioner is
operated according to the present invention; and
[0028] FIG. 6 is a flowchart showing a method for detecting a
mis-connected state between the communication lines for a
multi-type air conditioner according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] Reference will now be made in detail to the preferred
embodiments of the present invention, examples of which are
illustrated in the accompanying drawings.
[0030] FIG. 4 is an exemplary view showing a construction of a
system for detecting a mis-connected state between communication
lines for a multi-type air conditioner according to the present
invention.
[0031] As shown, the system for detecting a mis-connected state
between communication lines of a multi-type air conditioner
according to the present invention, comprises an indoor unit pipe
temperature detection unit 100 for detecting a temperature of an
indoor unit refrigerant pipe (will be referred to as `indoor unit
pipe`), a microprocessor 200 for controlling an opening of an
electronic expansion valve based on a temperature detected by the
indoor unit pipe temperature detection unit 100, comparing a
temperature response characteristic of the indoor unit pipe with a
preset temperature response characteristic of a normal indoor unit
pipe according to an opening of the electronic expansion valve, and
thereby judging whether communication lines are mis-connected to
one another or not, a display unit 400 for outputting error
information indicating a mis-connected state between the
communication lines, and a storage unit 300 for storing the preset
temperature response characteristic of the normal indoor unit pipe.
The indoor unit pipe temperature detection unit 100 comprises an
inlet temperature detection unit for an indoor unit pipe 110, and
an outlet temperature detection unit for an indoor unit pipe 120.
As the display unit 400, a screen, a display lamp, or a buzzer for
indicating a mis-connected state of the communication lines to a
user may be used.
[0032] An operation of the system for detecting a mis-connected
state between communication lines of a multi-type air conditioner
according to the present invention will be explained.
[0033] In the present invention, a throttling degree and a flow
amount of a working fluid are changed, and thereby a pipe
temperature is also changed. When the communication lines are
mis-connected to one another, an outdoor unit for receiving a
working fluid and an outdoor unit for receiving a control command
are not consistent with each other. Accordingly, a temperature
response characteristic of an abnormal pipe is different from that
of a normal pipe according to an opening of an electronic expansion
valve. By comparing the temperature response characteristic of the
normal pipe with the temperature response characteristic of the
abnormal pipe, a mis-connected state between the communication
lines can be detected.
[0034] More specifically, when the multi-type air conditioner is
initially driven, an opening of the electronic expansion valve is
controlled based on a temperature of the indoor unit pipe detected
by the indoor unit pipe temperature detection unit 100. Then, a
temperature response characteristic of the indoor unit pipe is
compared with a preset temperature response characteristic of a
normal indoor unit pipe according to an opening of the electronic
expansion valve. Then, the microprocessor 200 judges whether the
temperature response characteristic of the indoor unit pipe is
consistent with the preset temperature response characteristic of a
normal indoor unit pipe according to an opening of the electronic
expansion valve for a preset time. If so, the microprocessor 200
displays a normally-connected state between the communication lines
and performs a normal operation. On the contrary, if the detected
response characteristic is not consistent with the preset response
characteristic, the system is stopped and error information
indicating a mis-connected state between the communication lines is
displayed on an additional display unit.
[0035] FIGS. 5A and 5B are exemplary views respectively showing a
temperature response characteristic of the indoor unit pipe when
the communication lines are normally connected to one another, and
a temperature response characteristic of the indoor unit pipe when
the communication lines are mis-connected to one another under a
state that the multi-type air conditioner is operated according to
the present invention.
[0036] As shown in FIGS. 5A and 5B, the response characteristic of
the present invention can be variously implemented by using the
microprocessor 200. That is, the response characteristic includes
an inlet temperature of an indoor unit pipe, an outlet temperature
of the indoor unit pipe, an inlet temperature pattern of the indoor
unit pipe, an outlet temperature pattern of the indoor unit pipe, a
superheating obtained by deducting the inlet temperature of the
indoor unit pipe from the outlet temperature of the indoor unit
pipe, or a superheating pattern. A preset response characteristic
according to an opening of the electronic expansion valve when the
system is in a normal state is stored in the storage unit 300.
[0037] For instance, when the communication lines are mis-connected
to one another, the response characteristic has an inlet
temperature pattern of the indoor unit pipe shown in FIG. 5B. On
the contrary, when the communication lines are normally connected
to one another, the response characteristic has an inlet
temperature pattern of the indoor unit pipe shown in FIG. 5A, and
the superheating has a certain pattern. Therefore, the
microprocessor 200 compares a temperature response characteristic
of the indoor unit pipe with a preset temperature response
characteristic of the indoor unit pipe, thereby judging whether the
communication lines are mis-connected to one another or not.
[0038] A method for judging a mis-connected state between
communication lines of a multi-type air conditioner by the
microprocessor 200 according to the present invention will be
explained.
[0039] 1) A mis-connected state between the communication lines can
be judged by using a superheating, that is a difference value
between an outlet temperature of the indoor unit pipe detected by
the indoor unit pipe outlet temperature detection unit and an inlet
temperature of the indoor unit pipe detected by the indoor unit
pipe inlet temperature detection unit. That is, the superheating is
calculated based on the inlet temperature of the indoor unit pipe
and the outlet temperature of the indoor unit pipe. Then, the
calculated superheating is compared with a preset superheating,
thereby judging whether the communication lines are mis-connected
to one another or not.
[0040] 2) The detected inlet temperature of the indoor unit pipe
and the detected outlet temperature of the indoor unit pipe are
respectively compared with the preset inlet temperature of the
indoor unit pipe and the preset outlet temperature of the indoor
unit pipe.
[0041] 3) A superheating, that is, a difference value between the
detected inlet temperature of the indoor unit pipe and the detected
outlet temperature of the indoor unit pipe is calculated. Then, the
calculated superheating is compared with a preset superheating.
Also, a pattern of the detected inlet temperature of the indoor
unit pipe is compared with a preset pattern of the inlet
temperature of the indoor unit pipe.
[0042] 4) A temperature pattern of the indoor unit pipe detected
for a certain time is compared with a preset temperature pattern of
the normal indoor unit pipe.
[0043] 5) The detected temperature pattern of the indoor unit pipe
is compared with a preset inlet temperature pattern of the normal
indoor unit pipe. Then, if the two temperature patterns are not
consistent to each other, the microprocessor controls error
information indicating a mis-connected state between the
communication lines to be displayed.
[0044] 6) A superheating, that is, a difference value between the
detected inlet temperature of the indoor unit pipe and the detected
outlet temperature of the indoor unit pipe is calculated. Then, the
calculated superheating pattern is compared with a preset
superheating pattern. If the two superheating patterns are not
consistent to each other, the microprocessor controls error
information indicating a mis-connected state between the
communication lines to be displayed.
[0045] 7) A superheating, that is, a difference value between the
detected inlet temperature of the indoor unit pipe and the detected
outlet temperature of the indoor unit pipe is calculated. Then, the
calculated superheating pattern is compared with a preset
superheating pattern. Also, the detected temperature pattern of the
indoor unit pipe is compared with a preset temperature pattern of
the indoor unit pipe. Then, if the two temperature patterns are not
consistent to each other, the microprocessor controls error
information indicating a mis-connected state between the
communication lines to be displayed.
[0046] FIG. 6 is a flowchart showing a method for detecting a
mis-connected state between the communication lines for a
multi-type air conditioner according to the present invention.
[0047] As shown, in the multi-type air conditioner having an
arbitrary outdoor unit and a plurality of indoor units connected to
the outdoor unit according to the present invention, a method for
detecting a mis-connected state between the communication lines of
the multi-type air conditioner will be explained.
[0048] First, a user operates the arbitrary outdoor unit and the
plural indoor units connected to the outdoor unit by selecting a
menu for initially driving the system (ST10, ST20).
[0049] Then, the microprocessor 200 controls an opening of the
electronic expansion valve based on an indoor unit pipe temperature
detected by the indoor unit pipe temperature detection unit, and
then detects a temperature response characteristic of the indoor
unit pipe according to the opening of the electronic expansion
valve (ST30). Prior to performing the initial driving, a
temperature response characteristic of a normal indoor unit pipe is
preset by an experiment to be stored in the storage unit 300. The
response characteristic can be variously derived by the
microprocessor 200. For instance, the response characteristic
includes an inlet temperature of the indoor unit pipe, an outlet
temperature of the indoor unit pipe, an inlet temperature pattern
of the indoor unit pipe, an outlet temperature pattern of the
indoor unit pipe, a superheating obtained by deducting the indoor
unit pipe inlet temperature from the indoor unit pipe outlet
temperature, or a superheating pattern.
[0050] Then, the microprocessor 200 compares the detected response
characteristic with the preset response characteristic, thereby
judging whether the two response characteristics are consistent
with each other or a difference value therebetween is generated
(ST40). The step of judging can be performed by the aforementioned
methods 1 to 7.
[0051] Finally, when the detected response characteristic is
consistent with the preset response characteristic, the
microprocessor 200 displays a normal state on the display unit 400
and performs a normal operation (ST50). On the contrary, when the
detected response characteristic is not consistent with the preset
response characteristic or a difference value therebetween is more
than a certain value, the microprocessor 200 controls the system to
be stopped and displays error information indicating a
mis-connected state between the communication lines on the display
unit 400 (ST60).
[0052] As aforementioned, in the present invention, the temperature
response characteristic of the indoor unit pipe according to the
opening of the electronic expansion valve is compared with the
temperature response characteristic of the indoor unit pipe. If a
difference value more than a certain value is generated between the
two response characteristics, it is judges that the communication
lines are mis-connected to one another. Then, an indoor unit from
which the mis-connection has been generated is fast detected, and
error information is displayed. Accordingly, the mis-connected
state between the communication lines is restored, thereby
preventing a damage of the system due to the mis-connection.
[0053] As the present invention may be embodied in several forms
without departing from the spirit or essential characteristics
thereof, it should also be understood that the above-described
embodiments are not limited by any of the details of the foregoing
description, unless otherwise specified, but rather should be
construed broadly within its spirit and scope as defined in the
appended claims, and therefore all changes and modifications that
fall within the metes and bounds of the claims, or equivalence of
such metes and bounds are therefore intended to be embraced by the
appended claims.
* * * * *